Grade Identification - possible 347 variant?

[kclim]

Was wondering if anyone could offer some advice on the following material.

Used as in a valve seat, operating at high temperatures (540 C)

Composition analysis was undertaken (XRF machine), giving the following results

Cr 17%
Ni 12.3%
Mo 1.4%
Nb 0.8%
V 0.9%
(Fe Balance)

Material is non-magnetic

Was wondering if anyone had any ideas what grade material this might be? It appears to be similar to a 347, but with V and Mo additions.

Also, does anyone have any ideas how we might weld it? (heat treatment, consumable?) At this time, we're thinking about using a NiCr3 or 347 consumable, and welding it like an austenitic stainless grade. However, the V content has us a little worried.

Thanks in advance

 

[mcguire]

The grade doesn't fit any of the alloys I can find from my sources of high temperature austenitic alloys. Manganese and nitrogen levels will be needed for positive ID. That V level suggests a powder metal alloy with the V put there for wear resistance at a level not easily done in wrought material.

Whoever finds this one, please tell us where you found this information.

Michael McGuire

http://stainlesssteelforengineers.blogspot.com/

 

[metengr]

kclim;
What type of valve - boiler stop valve, turbine throttle valve, pump, etc?

 

[btrueblood]

About the closest thing out there is CG6MN cast stainless, but with too much Nb and V, and not enough Cr. Also, as mcquire says, we need to know Mn and N levels (Si too maybe)? This was from a matweb composition search bracketing nickel and vanadium percentages.

Component Wt. %
C Max 0.06
Cr 20.5 - 23.5
Fe 51.9 - 62.1
Mn 4 - 6
Mo 1.5 - 3
N 0.2 - 0.4
Nb 0.1 - 0.3
Ni 11.5 - 13.5
P Max 0.04
S Max 0.03
Si Max 1
V 0.1 - 0.3

 

[EdStainless]

I can't find my x-ray peak overlap chart right now, but I am guessing that this a low energy, low precision analysis.
I have seen stabalized 316 chemistries, but this looks wrong to me also.
We need better numbers.
Is there a chance that this item was coated? That could mess up the analysis.

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Rust never sleeps
Neither should your protection

http://www.trent-tube.com/contact/Tech_Assist.cfm

 

[rolledalloy]

Nitronic 50 (UNS S20910) is
22%Cr
12.5% Ni
2% Mo
5% Mn
0.2% Cb
0.2% V
0.3% N

Its close but not quite right.

Also there is a UNS S21500 or EN 1.4893 (Tradename Esshete 1250)

10% Nickel
15% Chromium
1% Mo
0.6% Mn
with Nb, V, and B additions.

These are listed in Rolled Alloys bulletin 1048, but we don't sell either of them.